| 摘要 |
PROBLEM TO BE SOLVED: To provide a producing method of fresh water and a producing device of fresh water, capable of recovering energy.SOLUTION: A producing method of fresh water includes: a step of supplying raw water A and dilution water B whose salt concentration is lower than that of the raw water A to an FO membrane device 13, mixing the dilution water B to the raw water A by filtration treatment and obtaining mixed water; and a step of supplying the mixed water to an RO membrane device 17 and producing fresh water D by filtration treatment. In the step of obtaining the mixed water, the positive osmotic pressure energy of the mixed water added in the FO membrane device 13 is used as a power source. A producing device 10c of fresh water includes: an FO membrane device 13 which is supplied with the raw water A and the dilution water B whose salt concentration is lower than that of the raw water A, and is for mixing the dilution water B in the raw water A by filtration treatment and obtaining the mixed water; and an RO membrane device 17 which is supplied with the mixed water and is for producing fresh water by filtration treatment. The positive osmotic pressure energy of the mixed water added in the FO membrane device 13 is used as a power source. |
